1) In position time graphs the slope increases as the object moves forward (or away from the sensor); the slope is 0 when the object is not moving; and the slope becomes negative as an object moves backwards (or towards the sensor). The line would cross the x-axis when an object goes behind the sensor but this did not occur in out lab because the sensor could only tell what object were in front of it.

2) In velocity time graphs the slope increases as the object increases velocity while moving forward (or away from the sensor); the slope is 0 when the object’s velocity is constant; and the slope becomes negative as the object increases velocity while moving backward (or towards the sensor). The line would cross the x-axis when the object changes direction. This did occur in our lab because we walked forward and then backward, changing our direction.